1. Field of the Invention
The present invention generally relates to image processing apparatuses, image processing methods, and programs, more particularly, to an image processing apparatus, an image processing method, and a program that enable viewers to receive high-quality image data.
2. Description of the Related Art
In terrestrial analog broadcasting which has hitherto been performed, standard definition (SD) images having an aspect ratio of 4:3 based on National Television System Committee (NTSC) composite signals are broadcast.
In addition to terrestrial analog broadcasting, terrestrial digital broadcasting has recently started. In terrestrial digital broadcasting, high definition (HD) images having an aspect ratio of 16:9 based on component signals are broadcast. Accordingly, by terrestrial digital broadcasting, images having a quality higher than images broadcast by terrestrial analog broadcasting can be provided.
It will take time, however, before broadcasting equipment, such as cameras for capturing HD images having an aspect ratio of 16:9, comes into widespread use since it is expensive.
Accordingly, in some broadcasting stations, only the format of composite-signal images to be broadcast in terrestrial analog broadcasting is adjusted to that of HD images to be broadcast in terrestrial digital broadcasting. More specifically, composite-signal images are first converted into component-signal images, and then, up-conversion is performed for increasing the number of pixels of the component-signal images through interpolation of pixels. Then, the resulting images with the adjusted format are broadcast.
Such HD images generated as described above are referred to as “pseudo-HD images”.
Since pseudo-HD images are images generated simply by converting composite images into component images, noise, so-called “cross-color” or “dot interference”, occurs in such pseudo-HD images. Additionally, pseudo-HD images are images generated by up-converting the component-signal images converted from the composite-signal images. Accordingly, noise, such as cross-color or dot interference, becomes even more noticeable by the up-conversion operation.
A technique for converting images into high-quality images by taking characteristics unique to composite signals into consideration has been proposed in, for example, Japanese Unexamined Patent Application Publication No. 10-056622.